Noncorrosive metal and article made therefrom



Patented May 24, 1932 UNITED STATES PATENT oFrIcE FELIX NICODEKO, OF NEW YORK, N. Y., ASSIGNOB TO INDESTBUCTIB LE"ALLOY COM- PANY, INC 01 NEW YORK, N. Y.,

A CORPORATION OF NEW YORK NONCORBOSIVE METAL AND ARTICLE MADE THEBEFBOM Ho Drawing.

This inventionrelates to alloys or alloy mixtures and methods of compounding the same; more particularly to metallic compo sitions and articles made therefrom which are non-corrosive and particularly resist corrosion when used as parts of electrolytic apparatus. 0

It is an object of my inventlon to provide a metallic mixture in the nature of an alloy which may be readily cast and formed into articles useful in electrolytic apparatus and be resistant to the corrosive action attending their use in this relation.

It is contemplated by my invention to provide electrolytic apparatus parts, such as storage battery terminal posts, clips, cables or parts of electrical battery posts or connections and a metal therefor, preferably as a surface sheathing or covering, which resists corrosion.

' Other objects of my invention reside in the provision of a metal composition in the nature of an alloy and a method of compounding the same whereby an alloy is obtained which has various industrial uses, particularly of value where it is desired to provide non-corrosive properties, especially that encountered in electrical connections.

Still further objects of my invention reside in the provision of a non-corrosive metal alloy and a method of preparing the same, made from the baser metals and which is substantially corrosion-resistant unden all conditions, particularly in connection with electrolytic, industrial apparatus, such as battery terminals, posts, clips, conductors, cables and the like.

I have found that the baser metals, such as antimony and tin, may be rendered substantially corrosion-resistant by alloying them while decom osing certain salts or by admixing uni ormly minute quantities, approaching traces of the residuum of decomposition of certain salts including copper sulfate and silver nitrate. Thus I have found that an alloy of antimony and tin may be rendered substantially corrosion-resistant by decomposing in the melt of this alloy, a mixture of silver nitrate and copper sulfate, resulting in what I believe is an inti- A pplicatiori filed December 9, 1929. Serial No. 412,918.

mate and fine distribution of the decomposition products of the salts about the alloy of antimony and tin, to render the antimony and tin passive and resistant to corrosion, especially when used in electrolytic devices, such as storage battery terminal posts, clips,

' nuts, cables or parts of an electrical battery,

there is decomposed during the formation of this alloy, very small quantities of equal parts by weight of silver nitrate and copper sulfate, the combined quantity of silver nitrate and copper sulfate being preferably added to the combined antimony .and tin content to constitute 2% of the alloy.

In the preparation of my alloy,antimony is first melted by heating at about 630 C. or just a few degrees above it. This material is permitted to cool slowly and then the tin is added. As the .tin melts at about 232 (3., solution of the two metals will be obtained well below the melting point of antimony. The combined heat retained by these metals will maintain both the tin and antimony in a molten. condition, slightly above 240 C. or thereabouts. At this point, there is first prepared an intimate mixture of silver nitrate and copper sulphate, comprising equal parts of these ingredients and the two constituting about 2% of the combined antimony and tin content. The salts so provided are intimately mixed with the molten alloy until the salts are completely decomposed, accompanied by a slight evblution of the gaseous material resulting from decomposition. The alloy in this form, while still molten and before solidification, should be utilized for casting in making the articles desired, such as battery terminal posts, electrodes, clips or other articles. If permitted to cool, the alloy should be formed into these articles by cold pressing or extrusion methods or by stamping.

If the alloy so prepared is to be re-melted for purposes of casting, just prior to the castioo I Ii

ing operation and while the alloy is still molten, an additional quantity of the silver nitrate and copper sulfate should be added.

The alloy so prepared will be found to be extremely corrosion-resistant, which is not characteristic of any of the baser metals when untreated. The baser metals are apparently pacified and resist corrosion if immediately cast or formed into the article after decomposition of the saline materials, comprising silver nitrate and copper sulfate. The alloy is particularly useful in connection with electrical apparatus or parts of such apparatus which are exposed to the corrosive action of acids or acid fumes, such as battery terminals, clips, nuts and smaller battery parts.

Having thus described my-invention and illustrated its use, what I claim as new and desire to secure by Letters Patent, is

' 1; The process of producing corrosion-resistant articles which comprises forming a molten batch of antimony and tin, intimately admixing therewith small quantities of silver nitrate and copper sulfate and then forming the metal so treated into articles.

2. The method of forming a corrosion-resistant alloy including antimony and tin, the steps which comprise first melting the antimony, fusing the tin therewith and then adding silver nitrate and copper sulfate while the alloy formed by the tin and antimony is below the melting point of antimony, intimately mixing the sllver nitrate and the coppersulfate just slightly above the melting point of tin and then forming the alloy so prepared into desired articles without again eating the batch.

3. The method of making a corrosion-resistant alloy which comprises melting antimony,'adding tin thereto to fuse the tin with the antimony below the melting point of antimony and then intimately mixing a combined mixture of silver nitrate and copper sulfate with the melt so prepared at about the melt ing point of tin.

As a new article of manufacture, an allo comprising tin and antimony and inclu ing the decomposition products of silver nitrate and copper sulfate at the melting point of the alloy.

5 s a new article of manufacture, an alloy mixture comprising antimony and tin in substantially equal parts and rendered inactive to corrosion by including decomposition products of silver nitrate and copper sulfate formed at substantially the lowest melting point ofthe alloy comprising the antimony and tin content. 7

In witness whereof I have hereunto signed my name this 25th day of November, 1929.

FELIX NICODEMO. 

